NQO1 and adenocarcinoma: In an older study in Taiwan, Lin et al. [20] showed that, similar to our study, the NQO1 (Pro187Ser) polymorphism was not strongly associated with LC risk in the general population; however, in individuals who smoked, the normal (wild-type) form of NQO1 increased the risk of adenocarcinoma by approximately 2.5-fold.